Discharge Status And Experimental Study Of WEDM In Variable Thickness Workpiece

As an excellent non-traditional machining method,WEDM has been widely used in aerospace,military,mold and other industrial manufacturing fields,and has obvious advantages in dealing with various irregular parts.In WEDM machining process,the stable and good interelectrode discharge is the guarantee of high efficiency and stable processing,thus highlighting the importance of discharging detection system,this is because the can be obtained by this system the change rule of wedm processing parameters,under the precondition of the analysis,processing and cutting properties of the emulsion medium,to improve the performance of discharging detection system,and provide data support to select the best parameters for later experiment.The voltage and current waveforms in wire-cut machining were obtained by the application experiment of edm wire-cut machining,and the representative voltage and current waveforms were screened out.Thus,five typical discharge waveforms in wire-cut machining were summarized,and the waveforms were used as the discriminating basis of discharge states.In this paper,the cutting experiment in emulsion is compared and analyzed,and then the voltage threshold is calculated by integral area method,so as to obtain the threshold setting in emulsion medium and ensure the accurate value of electrical signal.Algorithm programming in detecting system,using the electrical signals obtained from the prophase research values,in combination with the SVM neural network programming learning,thus to classify five kinds of discharge forecast,the SVM neural network has the character of parameter optimization at the same time,the use of this characteristic can be more accurately distinguish five kinds of discharge state,to further improve the identification accuracy.In terms of the construction of the detection system platform,the electrical signals obtained in the experiment are collected and transmitted through external acquisition elements,and various functional modules are built by the LAB VIEW virtual platform to detect the gap discharge status in real time.The addition of historical fault query module makes the detection system function more complete.Detection system application experiment is mainly divided into two parts,the first part in emulsion roughing variable thickness workpiece positive cutting of single factor experiment,the rough machining four main processing parameters(such as pulse width,peak current,pulse width ratio,workbench no-load speed)of three processing quality evaluation indexes(surface roughness,cutting speed and spark rate distribution)affect the trend;The second part carries out the reverse cutting verification experiment of workpiece with variable thickness,and obtains the best parameters through analysis and comparison,so as to guide the improvement of process index.